Extends the SQL store to support v2 (taproot) channel announcements:
- Add version validation in AddChannelEdge
- Store v2-specific fields: FundingPkScript, MerkleRootHash, Signature
- Update buildEdgeInfoWithBatchData to reconstruct v2 channels from DB
with optional bitcoin keys and funding script handling
- Add WithMerkleRootHash edge modifier for ChannelV2Fields
This commit extends ChannelEdgeInfo to support v2 (taproot) channel
announcements by adding:
- MerkleRootHash for the optional Merkle tree commitment
- ExtraSignedFields for additional signed TLV fields
- ChannelV2Fields struct to encapsulate v2-specific optional fields
- NewV2Channel constructor for creating v2 channel edges
- FundingPKScript handling for MuSig2 key aggregation with optional
taproot tweaks
Add FundingPKScript() method that returns the funding output's
pkScript for the channel. The implementation is version-aware:
- V1: generates a 2-of-2 multisig P2WSH script from the two bitcoin
keys
- V2: will use taproot script (to be implemented)
This encapsulates the script generation logic and makes it clear
which bitcoin keys are being used. Replaces direct calls to
genMultiSigP2WSH with the cleaner method call.
Since not all will be required for V2 channels.
Wrap BitcoinKey1Bytes and BitcoinKey2Bytes in fn.Option since these
fields are only required for v1 channel announcements. V2 channels may
or may not have bitcoin keys present in their announcement.
NewV1Channel constructor wraps the bitcoin keys with fn.Some().
All access sites updated to unwrap the options, using UnwrapOr for
non-critical paths and UnwrapOrErr where the keys must be present
(e.g., KV serialization, ToChannelAnnouncement).
So that we have one place that converts from our `models` struct to the
`lnwire.ChannelAnnouncement` struct.
The commit also refactors netann.CreateChanAnnouncement to only take a
ChannelEdgeInfo and get the proof from there instead of needing the
proof to be passed in separately.
Add ToChannelAnnouncement() method to ChannelEdgeInfo that converts
the model struct to a lnwire.ChannelAnnouncement1 message. This:
- Centralizes the conversion logic in one place instead of scattered
across multiple call sites
- Validates that AuthProof is present (can't create announcement
without proof)
- Currently only supports v1 channels, returning error for v2
Refactor netann.CreateChanAnnouncement to use this helper and remove
the separate chanProof parameter since proof is now accessed from
within ChannelEdgeInfo. This improves encapsulation and reduces
parameter count.
This makes it clear what fields must/can be set for a V1 channel.
Introduce NewV1Channel constructor to create v1 channel edges with
proper initialization and validation. The constructor:
- Takes required fields (chanID, chainHash, node keys) as parameters
- Takes v1-specific fields (bitcoin keys, extra opaque data) via
ChannelV1Fields struct
- Accepts optional fields (capacity, channel point, features, proof)
via functional options (WithCapacity, WithChannelPoint, etc.)
- Validates that if an AuthProof is provided, its version matches the
channel version
This makes it clear which fields are required vs optional for v1
channels and prevents incorrectly initialized channel edges. All
tests and production code updated to use the constructor.
And set it to V1 version everywhere.
Add a Version field to ChannelEdgeInfo to distinguish between v1 and
v2 channel announcements. Set it to GossipVersion1 for all existing
channels.
Both KV and SQL stores now validate that only v1 channels are
currently supported, returning an error for v2 channels. The KV store
automatically sets version to v1 when deserializing (since all
persisted channels in KV format are v1).
This versioning is essential for handling the different field
requirements and validation logic between v1 and v2 channels.
Replace [33]byte with route.Vertex for NodeKey1Bytes, NodeKey2Bytes,
BitcoinKey1Bytes, and BitcoinKey2Bytes in ChannelEdgeInfo. Since
route.Vertex is defined as [33]byte, this change is functionally
equivalent but provides better type safety and consistency with the
rest of the routing subsystem.
OtherNodeKeyBytes is also updated to return route.Vertex.
Both NodeKey1 and NodeKey2 methods had the same race condition as the
Node.PubKey method, where concurrent calls could race to write to the
cached fields.
Remove the caching for the same reasons: parsing overhead is minimal
and doesn't justify the complexity and race risk.
In this commit, we move the serialisation details of a channel's
features to the DB layer and change the `models` field to instead use a
more useful `*lnwire.FeatureVector` type.
This makes the features easier to work with and moves the serialisation
to where it is actually used.
In preparation for an upcoming commit which will move all channel
funding tx validation to the gossiper, we first move the helper method
which helps build the expected funding transaction script based on the
fields in the channel announcement. We will still want this script later
on in the builder for updating the ChainView though, and so we pass this
field along with the ChannelEdgeInfo. With this change, we can remove
the TapscriptRoot field from the ChannelEdgeInfo since the only reason
it was there was so that the builder could reconstruct the full funding
script.
All the structs defined in the `channeldb/models` package are graph
related. So once we move all the graph CRUD code to the graph package,
it makes sense to have the schema structs there too. So this just moves
the `models` package over to `graph/db/models`.
Elle Mouton